Broken:
- The editor does not work. You type things in, it forgets them, it comes out different, you switch between HTML and VISUAL and it loses stuff

To be really useful:
- ability to have multiple email lists
- ability to add images (with a simple button) to the email editing
- ability to save previous emails, in a list, so you have a history and can start new emails by editing previous ones

It is clean and simple and there is nothing else out there that can do this. So I really hope you take this to the next step!